Today, powdered nutritional compositions such as infant or follow on formula and growing up milks are manufactured by more than a dozen firms in 40-50 processing plants worldwide. Infant formula, follow on formula and growing up milks are preferably produced and sold as powders as this reduces transportation costs and increases the shelf life of the products. These formulations for infants and young children have to comply with regulations which allow for the use of only a limited number of ingredients which should or may be present within narrow ranges. Any changes beyond the regulatory nutrient requirements have to be notified to the regulatory bodies which have the authority to take compliance action if needed.
Hitherto, the main challenges the infant formula manufacturers are to come as close to human milk as possible, when taking into account the composition. Standard formulas have been subjected to high pressure homogenization steps yielding lipid globules with a mode diameter based on volume of less than 0.5 μm. Such formula with small lipid globules are typically preferred as these form a stable emulsion in the liquid form. It was found in WO 2010/027258 that formulas with large lipid globules, such as having a volume-weighted mode diameter of above 1 μm, and which are more similar to the lipid globules in unprocessed human milk, have beneficial health effects. The inventors in WO 2010/027258 provided ways to provide powdered formulas based on these larger lipid globules.
The powders should be easily dissolvable (i.e. reconstitutable) with water to a ready to drink liquid. They should not show a separation of different particles during transport and storage, as this may result in a nutrient imbalance over the time of use. The powder should also be easily flowable in order to facilitate packaging in the factory and enable easy handling and dosing by the end user. Some of these problems are easy dosing by preventing clumping and to ease dissolving of the powder in water which is related to a particle structure and size distribution. This remains to be a challenging task for the manufacturers. Both moisture and fat present in powdered infant formula potentially contribute to caking. According to the instruction manuals provided with the commercial infant formulas, the end user should prepare a milk bottle by measuring the amount of powder using a scoop or spoon, and dispersing the pre-determined amount in water at the desired temperature. In US 2008/0041861 is an example thereof. If the powder does not have good flowability properties and is sticky, the scoops or spoons may become coated with powder.
In the art there is thus a need to avoid or minimize lumping and cohesion particularly when dispensing the formula in water. Not only in the household, but also in the factory the cohesiveness of the powder should be low and the flowability of the powder high in order to facilitate filling the cans and the like. In production, the problems of cohesion and caking of these powders lead to significant costs.